i2c.c

Go to the documentation of this file.

/****************************************************************************
 * Copyright (C) 2015 Sensorian
 *                                                                          *
 * This file is part of Sensorian.                                          *
 *                                                                          *
 *   Sensorian is free software: you can redistribute it and/or modify it   *
 *   under the terms of the GNU Lesser General Public License as published  *
 *   by the Free Software Foundation, either version 3 of the License, or   *
 *   (at your option) any later version.                                    *
 *                                                                          *
 *   Sensorian is distributed in the hope that it will be useful,           *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of         *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          *
 *   GNU Lesser General Public License for more details.                    *
 *                                                                          *
 *   You should have received a copy of the GNU Lesser General Public       *
 *   License along with Sensorian.                                          *
 *   If not, see <http://www.gnu.org/licenses/>.                            *
 ****************************************************************************/

#include <stdlib.h>
#include "i2c.h"

void I2C_Initialize(unsigned char address)
{                       
    if (!bcm2835_init())                        //Configure I2C pins
    {
        printf("BCM libray error.\n");
    }
    bcm2835_i2c_end();      //Close I2C peripheral to reconfigure it
    
    bcm2835_i2c_begin();                        //Set pins as I2C
    bcm2835_i2c_set_baudrate(baudrate);         //Set I2C baudrate
    bcm2835_i2c_setClockDivider(BCM2835_I2C_CLOCK_DIVIDER_2500);        //100 Khz
    bcm2835_i2c_setSlaveAddress(address);   //Set device address
}

void I2C_WriteByte(char bdata)
{   char data = bdata;
    bcm2835_i2c_write(&data, 1);
}

void I2C_WriteByteRegister(unsigned char reg,unsigned char data)
{
    unsigned char wr_buf[2];

    wr_buf[0] = reg;
    wr_buf[1] = data;

    bcm2835_i2c_write((const char *)wr_buf, 2);
}

void I2C_WriteWordRegister(unsigned char reg, unsigned char* data)
{
    unsigned char wr_buf[3];
    
    wr_buf[0] = reg;
    wr_buf[1] = data[0];
    wr_buf[2] = data[1];

    bcm2835_i2c_write((const char *)wr_buf, 3);
}

void I2C_WriteByteArray(char reg, char* data, unsigned int length)
{
    char* wr_buf = (char*) malloc(sizeof(char) * length);
    if (wr_buf==NULL) 
    {
        printf("Error allocating memory!\n"); //print an error message
    }
    
    wr_buf[0] = reg;
    for(unsigned int i = 1;i<length;i++)
    {
        wr_buf[i] = data[i];
    }

    bcm2835_i2c_write((const char *)wr_buf, length);
}

unsigned char I2C_ReadByteRegister(char reg)
{
    char val = 0;
 
    bcm2835_i2c_read_register_rs(&reg,&val,1);
    
    return val;
 }
 
void I2C_ReadByteArray(char reg,char *buffer,unsigned int  length)
{   
    bcm2835_i2c_read_register_rs(&reg,buffer,length);
}

unsigned int I2C_ReadWordRegisterRS(char reg)
{
    char cmd[1] = {reg}; 
    char receive[2] = {0};
    bcm2835_i2c_write_read_rs(cmd,1,receive,2);
    
    return (receive[0]<<8)|receive[1];
}

unsigned int I2C_ReadWordPresetPointer(void)
{
    char val[2] = {0}; 
    bcm2835_i2c_read(val,2);
    unsigned int data = (val[0] << 8)|val[1];
    
    return data;
 }
 
 void I2C_Close(void)
 {
    bcm2835_i2c_end();
}